tbuckley/cabot-search huggingface dataset:
Abstract P1011: Pharmacological Targeting Of Tip60 For Heart Regeneration And Repair
Authors: Xinrui Wang, Katherine Kulik, Tina C Wan, Amelia Lauth, John W Lough, John A Auchampach
Journal: Circulation Research (2022)

In recent decades, many cardiovascular diseases have been ascribed to acetylation-dependent regulatory mechanisms, as revealed by the beneficial effects of targeting de-acetylase proteins. By contrast, we are targeting the acetyltransferase Tip60 (Tat-interactive protein 60 kD), a pleiotropic tumor suppressor encoded by the Kat5 gene. Using a murine genetic model, we recently reported that cardiomyocyte (CM)-specific disruption of Kat5 markedly protected against the damaging effects of myocardial infarction (MI). To establish therapeutic relevance, we have begun to evaluate the potential cardioprotective effects of TH1834, a small MW drug designed to specifically target the acetyltransferase domain of Tip60. Daily systemic administration of TH1834 on days 3-16 post-MI efficiently preserved cardiac function for up to 28 days post-MI, which was accompanied by reduced scar formation, diminished CM apoptosis, and activation of CM cell-cycle in the absence of CM hypertrophy. Subsequent gene ontology enrichment analysis of transcriptome sequencing data revealed that, among a total of 2,051 differentially expressed genes, 154 cell-cycle regulators and 96 apoptotic markers were altered by TH1834 treatment at day 10 post-MI; significant transcriptional changes in genes involved in cardiac muscle contraction, CM differentiation processes, and responses to ischemia/hypoxia were also identified. These data demonstrate that TH1834 administration promotes retention of post-MI function via enhanced remuscularization and by inhibiting cell death, supporting the translational potential of targeting Tip60 as a novel treatment for ischemic heart disease.
Abstract P1113: Ploidy Reversal As A Postnatal Developmental Program In Murine Hearts
Authors: Samantha K Swift, Mary E Kolell, Alexandra L Purdy, Michael A Flinn, Caitlin C O'Meara, Christoph D Rau, Michaela Patterson
Journal: Circulation Research (2022)

Polyploidization is a normal cellular adaptation for a variety of cell types in mammals, including cardiomyocytes (CMs); however, the development of polyploidization understudied. Recent work suggests that genetics contribute to diverse displays of ploidy in the adult murine heart. Therefore, we hypothesized that the developmental progression to reach differing end-states may similarly be affected. Here, we assessed CM endowment, cell cycle, and ploidy temporally across two diverse inbred mouse strains, A/J and C57Bl/6J. Consistent with previous work, C57Bl/6J hearts displayed rapid cell cycle activation in the first postnatal week largely coinciding with the first round of endomitosis. Total CM numbers are relatively unchanged after P7, while final ploidy states are generally constant from P14 on. In contrast, A/J mice displayed depressed cell cycle activation in the first week of life. Polyploidy in A/Js reaches its peak at P21, whereby only ~3.5% of CMs remained mononuclear and diploid. Interestingly, from 3-6 weeks of age, we observed a dramatic expansion of total CM numbers and of the 1x2N subpopulation to ~8%, which could not be explained by proliferation of the residual diploid population. Instead, the expanded diploid population appears to come from a polyploid CM. This finding was confirmed by analysis identifying a population of CMs which had definitively completed cytokinesis by 6 weeks which was not present at 3 weeks. We believe this is the first report of ploidy reversal by a mammalian CM, a phenomenon first observed by the hepatocyte field. Ongoing single nuclear RNA seq is examining the transcriptomic differences between A/J and C57Bl/6J CMs at P21 to identify this unique “primed” population competent to undergo ploidy reversal. Preliminary results from this study suggest that AJ CM nuclei, regardless of their ploidy, are more likely to be in the cell cycle in comparison to C57. Understanding the developmental paths to end state CM endowment and ploidy states can help us understand the biology of organ size and reciprocally can be applied to stimulating regeneration.
Abstract P3030: Fundc1 Mediated Mitochondrial Protein Import As A Novel Mechanism Exacerbating Dilated Cardiomyopathy
Authors: Fujie Zhao, Ganesh Satyanarayana, Zhaohua Cai, Jian Li, Yang Wu, Jianli Zhao, Zheng Zhang, Xin-liang Ma, Yajing Wang, Ming-Hui Zou
Journal: Circulation Research (2022)

Background: Dilated cardiomyopathy (DCM) is a common cause of heart failure and an indication for heart transplantation worldwide. FUN14 Domain Containing 1 (FUNDC1), a canonical mitophagy receptor and mitochondria-associated ER membranes (MAMs) protein, plays an essential role in ischemic heart disease. However, the role of FUNDC1 in DCM remains unidentified. The current study attempted to clarify whether and how FUNDC1 regulates DCM development. Methods: Cardiomyocyte-specific F UNDC 1 gene knockout (CM-FUNDC1 KO) mice were generated to study the impact and potential mechanisms of FUNDC1 in the heart. Mitochondria were isolated from heart tissues, primary mouse neonatal/adult cardiomyocytes, or H9C2 cell lines to probe the role of FUNDC1 in mitochondrial protein import (MPI). Results: All CM-FUNDC1 KO mice developed severe DCM spontaneously and died before 15 months old. The expression of MPI-associated proteins was significantly upregulated in the hearts of CM-FUNDC1 KO mice. Experiments with purified mitochondria demonstrated that MPI efficiency was enhanced by CM-FUNDC1 KO, whereas reduced by FUNDC1 overexpression in an autophagy-independent fashion. We further identified that FUNDC1 selectively downregulated the TIM23 complex without altering other MPI translocases (e.g., TOM20, TIM22 complexes). Downregulation of subunits of TIM23 complex partly reversed the FUNDC1 KO-induced MPI enhancement. Importantly, we demonstrated that FUNDC1 selectively inhibited the import of nuclear gene-encoded respiratory subunits on complex I, IV but not on complex II, III, V or mitochondrial gene-encoded subunits. Finally, FUNDC1 deleted cells exhibited enlarged cell size, retarded cell growth, impaired oxygen consumption rate, and increased mitochondrial superoxide level. All of these phenomena were partly reversed by silence TIM23 complex or reproduced by TIM23 complex overexpression. Conclusions: We demonstrate for the first time that: 1) MPI system plays an important role in the progress of DCM; 2) FUNDC1 is a novel negative regulator of MPI via TIM23 pathway; and 3) FUNDC1 is a promising therapeutic target for DCM.
Abstract P1020: Differential Contribution Of Bone Marrow Cells To The Heart In Steady-state And After Repetitive Ischemia
Authors: Parisa Shabani, Lindsay Shockling, Molly Enrick, Chris Kolz, Vahagn A Ohanyan, Liya Yin, William M Chilian
Journal: Circulation Research (2022)

Multiple studies have implicated the important role of migration of bone marrow (BM)-derived cells in heart after ischemia. Various BM-derived cells have been demonstrated to exert beneficial or detrimental effects in ischemia. But the response of BM to repetitive ischemia (RI) and the difference in contribution of this heterogenous population to the heart after RI remain elusive. Here, we applied an occluder on the left anterior descending coronary arteries of rats and they went under RI over a period of 10-17 days. This RI model induced coronary collateral growth and increased myocardial blood flow in the ischemic region after 10-17 days. We performed single- cell RNA sequencing and analysis of 24103 bone marrow transcriptomes isolated from the heart and bone marrow of rats in steady-state and after RI. Unsupervised clustering of cardiac neutrophils revealed 28 major clusters and 16 different cell types. Compared to steady state heart, proportion of BM derived macrophage mainly CD163 positive population was increased in the heart after RI. The proportion of BM derived natural killer cells was decreased markedly in the RI group. There was a slightly higher percentage of BM derived endothelial cells and lower smooth muscle cell and fibroblast in the RI group. While neutrophil degranulation, leukocyte activation, leukocyte migration are the major biological pathways in both groups, RI group showed activation of regeneration. We report heterogeneity of BM cells migrated to the heart during RI and redefine the BM that respond to heart ischemia and participate in induction of angiogenesis after RI.
Abstract P2026: S100a1 Protects Cardiomyocytes From Hypertrophic Growth By Controlling The De-novo Synthesis Of Contractile And Mitochondrial Protein Programs
Authors: Michael Egger, Manuel Glaser, Andreas Jungmann, Azmal A Syed, Jeroen Krijgsveld, Martin Busch, Rebecca Wade, Patrick Most
Journal: Circulation Research (2022)

Background and Hypothesis: Loss of S100A1 expression in heart failure contributes to adverse cardiomyocyte (CM) remodeling via an unknown molecular mechanism. Conversely, the antihypertrophic effect of viral-based restoration of S100A1 expression in diseased hearts is not understood yet. We hypothesized that S100A1 may directly interfere with mRNA translation in CMs. Methods and Results: An unbiased mass spectrometry/affinity purification approach using human recombinant S100A1 protein as a bait and murine S100A1 -/- knock-out CM homogenates as prey identified the translation initiation factors EIF4G, EIF2b, RPS6 and PABP as targets for Ca 2+ -bound (holo) S100A1 protein, amongst other translational regulators. Computational modeling revealed top-scoring binding modes for holo-S100A1’s C-terminus in close proximity to RPS6’s ser-235/236 phosphorylation site harboring domain, and PLA detected S100A1/RPS6 complexes in neonatal ventricular cardiomyocytes (NVCMs). siRNA silencing of S100A1 in NVCMs caused a significant increase in cell size (+44%*) and fetal gene expression (e.g. MYH7 4.2-fold*) with a prompt enhancement of the de-novo protein synthesis rate (+89%*), as assessed by IF, RT-PCR and puromycin incorp. up to 48h (n=3-5, *P&lt;0.05 vs contr). Although phospho-specific IB revealed an increase in RPS6-ser235/236 phosphorylation (+38%, n=10, P&lt;0.05) due to S100A1 knock-down, the activity of the upstream Akt/mTORC2 pathway remained unaltered. A nascent proteome analysis unveiled the significant increase and decrease in the de-novo translation of 554 and 17 proteins (FC&gt;1.5), respectively, in S100A1-silenced NVCMs vs contr. with e.g. MYH7, ALC-1, ACTN2 or Nppb in the top 10 newly synthesized proteins. Heart muscle contraction and metabolism-related GO-terms (e.g. myofibril assembly or FA oxidation and OXPHOS) characterized the top 100 upregulated proteins. Conclusion: This is the first study providing evidence for an impact of S100A1 on the mRNA translation machinery in CMs by inhibiting translation of contractile and mitochondrial protein programs required for hypertrophic growth. S100A1 may mechanistically interfere with molecular factors of the translation initiation machinery, which warrants further investigation.
Transplantation of the lung
Authors: T Higenbottam, BA Otulana, J Wallwork
Journal: European Respiratory Journal (1990)

The introduction of cyclosporine as a highly effective immunosuppressive agent and the development of new techniques for heart-lung and lung transplantation have led to a new treatment for a wide range of fatal cardiopulmonary diseases. Indications for surgery are now becoming clear, together with major contra-indications. Suppurative lung disease, such as cystic fibrosis, can be effectively treated by heart-lung transplant (HLT). A whole new field of pulmonary medicine is emerging to provide the physiological monitoring and diagnostic techniques for major complications such as opportunistic lung infection and pulmonary rejection. Obliterative bronchiolitis, a consequence of frequent and severe rejection, still provides a major challenge to the immunological scientist and respiratory physician. Lung transplantation, by disrupting the vascular supply and innervation of the lung, is raising major questions about the generally accepted beliefs of regulation of breathing and pulmonary mechanics. Finally, as the survival rate improves beyond the current 50% at 3 yrs, lung transplantation will perhaps present further challenges to our understanding of the pathogenesis of various diseases such as asthma and cystic fibrosis.
Abstract P2009: MPTM1: A Cardiac-Enriched Microprotein That Is Upregulated During Heart Failure
Authors: Michael L Kamradt, Catherine A Makarewich
Journal: Circulation Research (2022)

Although they were originally misclassified as lncRNAs due to oversights in genome annotation methods, microproteins—proteins with open reading frames (ORFs) of 150 amino acids or less—execute critical roles in heart and skeletal muscle. We have identified a novel microprotein, MPTM1, that is enriched in cardiac and skeletal muscle tissues. The MPTM1 amino acid sequence is strongly conserved across multiple species, which indicates that it is a functional microprotein that has been maintained in response to evolutionary pressure. Genome-wide association studies (GWAS) of patients have demonstrated that MPTM1 is upregulated during heart failure. Additionally, MPTM1 expression strongly increases during skeletal muscle differentiation and maturation. In the present study, we assessed the hypothesis that MPTM1 promotes heart and skeletal muscle homeostasis using both in vitro and in vivo gain- and loss-of-function approaches. Furthermore, we generated C2C12 myoblast and NIH3T3 fibroblast cell lines null for MPTM1 using CRISPR/Cas9 gene editing methods. MPTM1 depletion in knockout cell lines resulted in striking membrane and nuclear abnormalities. Additionally, MPTM1 null C2C12 cells exhibited defects in myoblast differentiation characterized by premature myosin expression, altered cellular architecture, abnormal nuclear distribution, and the accumulation of intracellular vacuoles. We further evaluated MPTM1 cellular function using CRISPR/Cas9 homology-directed repair (HDR) to insert tandem affinity tags (3XHA-V5 or 3X FLAG) into the MPTM1 locus to assess binding partners in vitro using immunoprecipitation and mass spectrometry. Our results provide strong evidence that MPTM1 is a multi-localizing protein that is differentially recruited to the cytosol, nucleolus, and mitochondria, indicating it may act as a key intracellular signaling effector in response to stress. Additional studies in MPTM1 null mice are ongoing and will provide critical insight into MPTM1 function in the heart at under normal physiologic conditions and in response to pathological stress.
Abstract P3020: Chronic Heart Failure As A Sequel After Severe Burn Injury - First Insight Into A Novel Pathological Heart-skin Axis
Authors: Gabriel Hundeshagen, Victoria Mertin, Philipp Thiele, Andreas Jungmann, Felix A Trogisch, Oliver Drews, Joerg Heineke, Sophie Van Linthout, Jens Fielitz, Manuel Mayr, Martin Busch, Ulrich Kneser, Patrick Most
Journal: Circulation Research (2022)

Background: We described chronic heart failure with preserved ejection fraction (HFpEF) as a long-term sequel in survivors of severe pediatric burn injury (BI) (Hundeshagen et al., Lancet Child &amp; Adolescent Health, 2017). Applying a widely used standardized scald injury rat model in burn research, we sought to uncover systemic and molecular pathomechanisms that may cause post-BI HFpEF development. Methods and Results: Male adolescent SD-rats were subjected to a 60% total body surface area full-thickness BI (B; 100% survival) or sham (S) procedure (each n=10) and characterized them up to 90 days (3, 7, 30 and 90d) by serial echocardiography (E), bulk myocardial NGS and -proteomics, RT-PCR, IB, histology (H) and plasma proteomics for cardiac performance and molecular alterations, respectively. B rats mirrored typical post-burn clinical traits as significant loss in body (-27%*) or skeletal muscle weight (-30%*) e.g., with elevated atrophy markers as Murf1 (5-fold*) throughout the observation period vs S (30d, *P&lt;0.05) Our focus on the heart revealed in vivo heart weight loss (-22%*), cardiomyocyte hypotrophy (-8%*) and diminished mTOR activity in B hearts (p/t-mTORC2 -43%*) vs S as well as significantly diminished left ventricular (LV) GLS with unchanged LV-EF. RT-PCR and H showed significant cardiac accumulation of cardiodepressive factors (i.e., S100A8 and A9) and e.g., granulocyte (MPO, &gt;3-fold*) infiltration as well LV fibrosis (2.2-fold*). Cardiac proteomics yielded e.g., neutrophil degranulation as lead GO-term. Serial blood and plasma proteomic and ELISA analysis indicated elevated WBC (+26%*) and levels e.g., of IL6, S100A8/A9, CH3L1 and other HF markers alike changes in human post-BI plasma samples. WGCNA for bulk myocardial NGS and clinical traits related activated immunological and pro-fibrotic pathways in post-BI hearts to cardiac dysfunction in B. Conclusion: The first ever report of the development of HFpEF as a novel systemic consequence of severe burn injury in a rodent model prepares the ground for further mechanistic and translational studies. Cardiac inflammation and fibrosis that negatively impact cardiac performance may be mechanistic key findings guiding further therapeutic studies and validation of post-BI HF biomarkers.
Neuron-specific enolase in the diagnosis of small-cell lung cancer with pleural effusion: a negative report
Authors: T Pettersson, M Klockars, B Froseth
Journal: European Respiratory Journal (1988)

We measured the concentration of neuron-specific enolase (NSE) and carcinoembryonic antigen (CEA) in the serum and pleural fluid of 53 patients with pleural effusions, including seven patients with small-cell lung cancer (SCLC). High levels (above 12.5 micrograms.l-1) of NSE in pleural fluid were observed in five patients with SCLC (sensitivity 71%). However, pleural fluid NSE levels were also increased in five patients with other types of cancer and in four patients with non-malignant inflammatory diseases (specificity 80%). We conclude that although SCLC with pleural effusion can be associated with elevated pleural fluid NSE activity, this increase in enzyme levels is not specific for malignancy.
Abstract P1135: Psme4 Degrades Acetylated Yap1 In The Nucleus Of Mesenchymal Stem Cells To Induce Cardiac Commitment
Authors: Somy Yoon, Yong S Kim, Gwang Hyeon Eom, Young Keun Ahn
Journal: Circulation Research (2022)

Intensive research has focused on minimizing the infarct area and stimulating endogenous regeneration after myocardial infarction. Our group elucidated that apicidin, a histone deacetylase (HDAC) inhibitor, robustly stimulates cardiac commitment of mesenchymal stem cells (MSCs) through acute loss of YAP1. Here we further studied the mechanism of this role of YAP1 in MSCs. We found that acute loss of YAP1 after apicidin treatment resulted in the mixed effects of transcriptional arrest and proteosomal degradation. Subcellular fractionation revealed that YAP1 was primarily localized in the cytoplasm. YAP1 was acutely relocalized into the nucleus and underwent proteosomal degradation. Interestingly, phosphor-S127 YAP1 was shuttled into the nucleus, suggesting that a mechanism other than phosphorylation governed subcellular localization of YAP1. Apicidin successfully induced acetylation and subsequent dissociation of YAP1 from 14-3-3, an essential molecule for cytoplasmic restriction. HDAC6 regulated both acetylation and subcellular localization of YAP1. An acetylation-dead mutant of YAP1 retarded nuclear redistribution upon apicidin treatment. We failed to acquire convincing evidence for polyubiquitination-dependent degradation of YAP1, suggesting that a polyubiquitination-independent regulator determined YAP1 fate. Nuclear PSME4, a subunit of the 26S proteasome, recognized and degraded acetyl YAP1 in the nucleus. MSCs from PSME4-null mice were injected into infarcted heart and aberrant sudden death was observed. Injection of immortalized human MSCs after knocking down PSME4 failed to improve either cardiac function or the fibrotic scar area. Our data suggest that acute ablation of YAP1 in the nucleus by the acetylation-dependent proteasome subunit PSME4 is mandatory for cardiac commitment of MSCs.
Abstract P1134: Activation Of Endogenous Transcription Factors By CRISPRa Mediates Cardiac Reprogramming
Authors: Benjamin P Keepers, Li Qian, Jiandong Liu, Samuel Shutt
Journal: Circulation Research (2022)

Studies of cardiac reprogramming - the conversion of fibroblasts to cardiomyocyte-like cells - have deepened our understanding of cell identity changes, and they hold promise for potential clinical application. At the core of most cardiac reprogramming approaches lie three transcription factors: MEF2C, GATA4, and TBX5 (MGT). Exogenous expression of MGT can convert fibroblasts into cardiomyocyte-like cells, but it is unknown if activation of endogenous MGT can mediate reprogramming, or if these reprogrammed cells would be phenotypically different. In this study, we implemented CRISPR-based gene activation (CRISPRa) for targeted activation of endogenous MGT in mouse and human fibroblasts. Transcriptional activation ranged from 10X-10,000X greater than the non-targeted control, varying by gene and target locus. In combination with miR-133 overexpression, CRISPRa of all three of the MGT factors induced cardiac reprogramming of human fibroblasts. Multiple combinations of guide RNAs were capable of mediating human reprogramming with varying efficiencies. Induced cardiomyocytes appear phenotypically different under immunofluorescence. Finally, we simplified the human CRISPRa platform by combining the guide RNAs into a single, multiplex vector. Cellular and molecular studies of this new reprogramming model may provide mechanistic insights into cell fate conversion.
Parenchymal emphysema measured by CT lung density correlates with lung function in patients with bullous disease
Authors: GA Gould, AT Redpath, M Ryan, PM Warren, JJ Best, EJ Cameron, W MacNee
Journal: European Respiratory Journal (1993)

In subjects with chronic obstructive pulmonary disease (COPD) computed tomographic (CT) lung density correlates with direct pathological measurements of the size of the distal airspaces, as well as with measurements of airflow limitation and impairment of the diffusing capacity. Thus, CT lung density can be used to quantify emphysema in life. We wanted to assess the use of CT scanning to detect and measure the extent of bullous lung, and to quantify the severity of emphysema in the non-bullous areas of the lungs. In patients with bullous emphysema (21 males and 2 females; aged 31-69 yrs; forced expiratory volume in one second (FEV1) 14-84% predicted; volume corrected diffusing capacity of the lungs for carbon monoxide (DLCO/VA) 17-114% predicted). CT lung density was measured in electromagnetic imaging (EMI) units. The extent of bullous emphysema correlated poorly with all respiratory function measurements. In contrast, the severity of emphysema in the non-bullous parts of the lungs, expressed as either the mean EMI number, or the EMI number of the lowest 5th percentile of the CT lung density histogram, correlated well with measurements of airflow limitation and diffusing capacity. Our findings, thus, suggest that in patients with bullae the major determinant of respiratory function is the severity of the emphysema in non-bullous lung, and that the extent of the bullae has less functional importance.(ABSTRACT TRUNCATED AT 250 WORDS)